1. Technical Field
The present invention relates to an electronic switching system having a plurality of processors performing operation, maintenance and status management of a plurality of processors, and more particularly, to a method of checking a status of each individual processor in an electronic switching system.
2. Background Art
In general, conventional electronic switching system such as disclosed in U.S. Pat. No. 5,105,420 for Method And Apparatus For Reconfiguring Interconnections Between Switching System Functional Units issued to Ardon et al. is a multi-processor system having an internal switching network, a plurality of processors each connected to the internal switching network and a maintenance processor. The maintenance processor typically provides the system-level interfaces required to operate, administer, and maintain the switching system. Periodically, the maintenance processor sequentially scans each individual processor through an internal switching network for status information of the processors connected to the internal switching network.
Conventional scheme for the electronic switching system to detect the status including any internal abnormality that occurs in each individual processor requires that the maintenance processor to periodically perform a message transmission and reception operation for checking the status of all the processors connected to the switching system. Abnormality of the processor, however, affects operation of the maintenance processor as a fixed load and may therefore give rise to a busy hour fault. Moreover, as a means to communicate with all the processors, the maintenance processor is typically arranged in a far path of the internal switching network. This arrangement, however, frustrates the efficiency of the internal switching network for the message communication. In addition, if status faults coincidentally occur in the plurality of processors simultaneously, a lot of change requests of the processor status table must be simultaneously received by the maintenance processor, and changing jobs must be carried out at the same time. This excessive overload of the maintenance processor frequently forces the maintenance module to be down. As a result, access to the electronic switching system can be cut off completely and operational functions such as data back-up or processor loading can be paralyzed.